The good news is, the cost is coming down, and we could see an explosion of new DIY energy opportunities over the coming decade. As with so many things, the biggest limiting factor appears to be our own imagination.

Case in point – consider the humble potato. Smithsonian Magazine reports that Israeli researchers at the Hebrew University of Jerusalem boiled a potato, wired it up to a copper cathode and a zinc anode, and used it to power LED lights for up to 40 days. The researchers envision using this simple setup, which costs 10% of a typical AA battery, to power cell phones and other personal electronics in remote or underdeveloped regions.

The science behind this gimmick is that the potato conducts electricity by behaving as a "salt-bridge" between the two metals. Any fruit rich in electrolytes (bananas and strawberries, to name two) do the trick as well. Because potatoes work so well as a catalyst, Smithsonian dubs them "basically nature’s version of battery acid." Potatoes were also used because of their relative abundance, says agricultural science professor Haim Rabinowitch.

Granted, this energy solution won’t likely find its way onto U.S. farms anytime soon, but it’s still proof positive that scientists are devoted to increasingly inventive ways to tap into renewable energy sources. In the meantime, take a moment to ponder the power of something as simple as a potato.